Sunday, April 18, 2010

Robins make up their songs in a series of verses. most of the time i hear them sing about 4 to 6 phrases or tweets per verse. Robins usually know about a dozen or two different kinds of tweets. Often at the end of each verse they will sing a very high pitched 'hissely'. When analyzed with a computer, we find that robins sing about 50 different kinds of hisselys. Odd. I don't remember how they learn their tweets, either from each other or they make them up as they mature. Either way, each robin knows a distinct set of tweets.

What are they saying? How carefully are they composing? According to studies reported by Donald Kroodsma, in his book "the singing life of birds" many birds definitely are composing as they go. Either learning from each other, reacting to each other... The brown thrasher has been recorded to know about a 1000 different tweets, which it sings in very quick succession, improvising many on the spot. A Charlie Parker of birds.